It has long been known to manufacture and utilize pressure sensitive adhesive stock for labels, tapes, films, closure systems and the like. Pressure sensitive adhesives are themselves well known and are available with a wide variety of properties depending on their end use. Pressure sensitive adhesives are especially useful in the manufacture and the application of labels because of their ability to form an immediate bond.
Typically, these labels will be die cut from a web of face material, and have printed indicia on an upper surface. The lower surface of the face material is coated with a layer of pressure sensitive adhesive. A release liner having a release coating is removably adhered to the adhesive coated side of the label for protection of the coated surface during shipping and storage. The release liner further serves as a means to deliver a label to the application site and as a means for applying the label to the product. This release liner is easily removed either manually or automatically at the site of end use and the adhesive, having a greater affinity for the face material than for the release liner, remains in tact on the label, thereby enabling the label to be attached to the desired surface. A protective coating or thin transparent plastic film is often applied to the top surface of the label for protection from disfiguration.
These labels are either manually or automatically applied to the desired surface by separating or removing the label from the release liner. The release liner is virtually useless after its removal from the labels and when used in large applications a substantial volume of liner is generated. Disposal and collection of this liner waste can be time consuming and a nuisance. Furthermore, because of its silicone coating, the release liner is not normally reusable or a candidate for most recycling projects. Additionally, the silicone coating often makes the liner slippery and if not substantially or immediately collected, the presence of any portion of this liner on the floor in or around the work station creates a potential safety hazard.
Similarly, the matrix removed from a web of die cut labels produces similar problems regarding collection and disposal. Since the matrix is coated with adhesive it is virtually unrecyclable with existing technology and often refused at waste collection sites.
Therefore, it is desirable to have a roll of pressure sensitive adhesive label material which is self wound and which eliminates the necessity of a release liner. Additionally, supplying such labels in a continuous web, separated by perforations, as opposed to die cutting each label, eliminates a potentially costly and time consuming step in the manufacture of such labels as well as generated waste matrix.
U.S. Pat. No. 4,886,680 discloses a method of applying an adhesive coating to one side of a web and a silicone coating to the opposite side of the web, thus supplying the web in a rolled form without a release liner. While this reference shows a method for producing a rolled web of pressure sensitive adhesive film, it lacks any teaching with regard to producing a web of pressure sensitive adhesive labels having a protective laminate releasable from the adhesive. This patent does not disclose any reuse of the release liner as the web's overlaminate layer and requires the purchase of special applicator equipment by the end user.
Therefore, based on the limitations and deficiencies in the known prior art, the present invention is subsequently presented.